Home Synthesis and Dimroth Rearrangement of 6-Cyano-l,2,4-triazolo- [4,3-a]pyrimidin-5- and 7-ones. A Novel Alkylation with Orthoesters and a New Participation of the Cyano Group in the Rearrangement
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Synthesis and Dimroth Rearrangement of 6-Cyano-l,2,4-triazolo- [4,3-a]pyrimidin-5- and 7-ones. A Novel Alkylation with Orthoesters and a New Participation of the Cyano Group in the Rearrangement

  • E. S. H. El Ashry , Y. El Kilany , N. Rashed , A. Mousaad and H. Assafir
Published/Copyright: June 2, 2014
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Zeitschrift für Naturforschung B
From the journal Zeitschrift für Naturforschung B Volume 53 Issue 10

Abstract

The cyclization products of 5-cyano-2-hydrazino-6-phenyl-3,4-dihydropyrimidin-4-one (6) with one carbon inserting agents have been confirmed to be of the 1,2,4-triazolo[4,3-a]pyrimidin- 5(8H)-ones type and not the respective 7-ones, by comparing their alkylated derivatives 10a, 11a, 27 and 28 with the product from the cyclization of the 3-methyl and 3-benzyl derivatives of 6. A novel alkylation process was found when triethyl orthoformate was used as a cyclizing agent. Dimroth rearrangement of 8, 14, 15, 24, 34 and 36 with 2% ethanolic KOH gave the respective triazolo[1,5-a]pyrimidinone 13, 18, 19, 25, 38 and 40, respectively. Using 10% ethanolic KOH led to a novel participation of the cyano group in the rearrangement whereby 8a gave 7-imino-5-phenyl-l,2,4-triazolo[1,5-a]pyrimidine 22

Keywords: Dimroth Rearrangment; Alkylation with Orthoesters; Cyano Group; Pyrimidine; Triazolopyrimidine
Received: 1998-6-3
Published Online: 2014-6-2
Published in Print: 1998-10-1

© 1946 – 2014: Verlag der Zeitschrift für Naturforschung

Articles in the same Issue

  1. Ubergangsmetall-substituierte Phosphane, Arsane und Stibane, LIX [1], Ein Addukt des Me3P-substituierten Ferrio-diphenylphosphans Cp(OC)(Me3P)Fe-PPh2 mit Methylisothiocyanat: Darstellung, Protonierung und Methylierung / Transition Metal Substituted Phosphanes, Arsanes and Stibanes, LIX [1]. An Adduct of the Me3P-Substituted Ferrio-diphenylphosphane Cp(OC)(Me3P)Fe-PPh2 and Methylisothiocyanate: Synthesis, Protonation, and Methylation
  2. Ubergangsmetall-substituierte Phosphane, Arsane und Stibane, LX [1]. Ferrio-(thiocarbamoyl)phosphane Cp(OC)2 Fe-P(Mes)[C(=S)-N(R)H] (R = Me, Et, f-Bu): Aufbau aus dem Ferrio-mesitylphosphan Cp(OC)2 Fe-P(Mes)H und Organoisothiocyanaten sowie Quaternisierung mit Alkylhalogeniden und Oxidation mit Schwefel / Transition Metal Substituted Phosphanes, Arsanes and Stibanes, LX [1]. Ferrio-(thiocarbamoyl)phosphanes Cp(OC)2Fe-P(Mes)[C(=S)-N(R)H] (R= Me, Et, r-Bu): Build-up from the Ferrio-mesitylphosphane Cp(OC)2Fe-P(Mes)H and Organoisothiocyanates, Quatemization with Alkyl Halides and Oxidation with Sulfur
  3. Phosphenium-Komplexe, 43 [1]. Ringöffnungsreaktionen der dreigliedrigen Phosphametallacyclen {PR2 = P(o-Tol)2, P(Ph)(o-Tol), P(Mes)[C(S)N(H)Et], P(/-Bu)[C(O)N(H)Et} / Phosphenium Complexes, 43 [1]. Ring-Opening Reactions of the Three-Membered Phosphametallacycles {PR1 = P(o-Tol)2, P(Ph)(oTol), P(Mes)[C(S)N(H)Et], P(r-Bu)[C(0)N(H)Et}
  4. Magnesium Bis[D(-)-Mandelate] Dihydrate and Other Alkaline Earth, Alkali, and Zinc Salts of Mandelic Acid
  5. The Basicity of Silylamines and Alkylamines: An Equilibrium Study of the Competitive Borane Adduct Formation
  6. Kristallchemische Beziehungen von CO6O2 [TeO4 (CoAsO5)2] zur Steinsalzstruktur von CoO mit einem Beitrag über magnetische Messungen an CO6O2[TeO4(CoAsO5)2] / Crystal Chemical Relations of Co6O2[TeO4(CoAsO5)2] to the Rocksalt Structure of CoO and a Contribution on Magnetic Measurements of Co6O2[TeO4(CoAsO5)2]
  7. Synthese, Kristallstruktur und Eigenschaften von Triguanidinium-tri--imidocyclotriphosphat-Monohydrat und Tetraguanidinium-tetra-/i-imidocyclotetraphosphat-Tetrahydrat, [C(NH2)3]3(PO2NH)3 · H2O und [C(NH2)3]4(PO2NH)4 · 4 H2O / Synthesis, Crystal Structure, and Properties of Triguanidinium Tri-/i-imidocyclotriphosphate Monohydrate and Tetraguanidinium Tetra-/i-imidocyclotetraphosphate Tetrahydrate, [C(NH2)3]3(PO2NH)3 · H2O and [C(NH2)3]4(PO*NH)4 · 4 H2O
  8. Untersuchungen an Polyhalogeniden, XXXVII [1]. Heptaiodide(3-) von Amminkomplexen des Chroms und Cobalts: Hexamminchrom(III)heptaiodid [Cr(NH3)6](I3)(I4) und die Tri-μ-hydroxo-bis[metall(III)-triammin]heptaiodide [(NH3)3 M(OH)3M(NH3)3](I3)2I mit M = Co, Cr / Studies o f Polyhalides, XXXVII [1]. Heptaiodides(3-) of Ammine Complexes of Chromium and Cobalt: Hexamminechromium(III) heptaiodide [Cr(NH3)6](I3)(I4) and the Tri-μ-hydroxo-bis[metal(III)-triammine] heptaiodides [(NH3)3M(OH)3M(NH3)3](I3)2I with M = Co, Cr
  9. Functionalized 1,1-Ethene Dithiolates as Ligands, V [1]. Synthesis and Crystal Structure of Palladium(II) and Platinum(II) Complexes with Dithioylidene Barbituric Acid Ligands. Molecular Structure of a 2,6-Diaminopyridine-Platinum(II) Barbiturate Complex
  10. Solvothermal Synthesis and Crystal Structure Determination of Tris- (ethyleneamine-ammonium) Tetraselenoantimonat: Non-Centrosymmetry Mediated by an Extended Unusual N-H···N Hydrogen Bonded Network?
  11. Thermische Zersetzung und Lösungskalorimetrie von Ammoniumeuropiumchloriden / Thermal Decomposition and Solution Calorimetry of Ammonium Europium Chlorides
  12. Photochemical Reductive Elimination of Nitrogen from Triazidogallium(III). Generation of Luminescent Gallium(I)
  13. Zur Existenz von [ReNCl4-nFn]- (n = 1-3) Nitridorhenat(VI)-Gemischt- ligandkomplexen -Eine EPR-Untersuchung / EPR Evidence of [ReNCl4-n FnJ– (n = 1-3) Nitridorhenate(VI) Mixed-Ligand Complexes
  14. Synthesis and Crystal Structure of N-[(15,4R)-2-Oxo-pinanyl]-β-alanine Methylester
  15. Synthesis and Conformation of Nucleoside 5'-S-Thiosulfates
  16. Niedere Hydrate aliphatischer primärer Amine. Neue Untersuchungen zu Bildung und Struktur [1] / Lower Hydrates of Aliphatic Primary Amines. New Studies of Formation and Structure [1]
  17. Synthesis and Dimroth Rearrangement of 6-Cyano-l,2,4-triazolo- [4,3-a]pyrimidin-5- and 7-ones. A Novel Alkylation with Orthoesters and a New Participation of the Cyano Group in the Rearrangement
  18. Synthesis and Thermal Properties of Twin Compounds, Alkanediacids 4-(4'-Cyano)-biphenyl Diesters
  19. Synthesis of Pyrrolo-, Thienopyrrolo-, Benzothienopyrroloquinolines as well as Triazoloindole Derivatives
  20. Ab initio MO Optimizations of Osmiumtetracarbonyldihydride and Metallacyclophanes with two Osmium Atoms and their Molecular Complexes with Different Guests
  21. Preparation and Crystal Structure of Cs4Nb2S11
  22. On the Metalation of 2,6-Dimethyl-4-tert-butyl-thiophenol
  23. Kristallstruktur des Oxo-Acetatkomplexes [Co7(μ4- O)2(O2CCH3)10(OPEt3)2] / Crystal Structure of the Oxo-Acetate Complex [Co7(μ4 -O)2(O2CCH3)10(OPEt3)2]
  24. Penol Catalyzed Claisen ortho Ester Rearrangment of Allylic Alcohols with Trimethyl-β-hoxy) ortho Propionate
https://doi.org/10.1515/znb-1998-1017
Keywords for this article
Dimroth Rearrangment; Alkylation with Orthoesters; Cyano Group; Pyrimidine; Triazolopyrimidine

Articles in the same Issue

  1. Ubergangsmetall-substituierte Phosphane, Arsane und Stibane, LIX [1], Ein Addukt des Me3P-substituierten Ferrio-diphenylphosphans Cp(OC)(Me3P)Fe-PPh2 mit Methylisothiocyanat: Darstellung, Protonierung und Methylierung / Transition Metal Substituted Phosphanes, Arsanes and Stibanes, LIX [1]. An Adduct of the Me3P-Substituted Ferrio-diphenylphosphane Cp(OC)(Me3P)Fe-PPh2 and Methylisothiocyanate: Synthesis, Protonation, and Methylation
  2. Ubergangsmetall-substituierte Phosphane, Arsane und Stibane, LX [1]. Ferrio-(thiocarbamoyl)phosphane Cp(OC)2 Fe-P(Mes)[C(=S)-N(R)H] (R = Me, Et, f-Bu): Aufbau aus dem Ferrio-mesitylphosphan Cp(OC)2 Fe-P(Mes)H und Organoisothiocyanaten sowie Quaternisierung mit Alkylhalogeniden und Oxidation mit Schwefel / Transition Metal Substituted Phosphanes, Arsanes and Stibanes, LX [1]. Ferrio-(thiocarbamoyl)phosphanes Cp(OC)2Fe-P(Mes)[C(=S)-N(R)H] (R= Me, Et, r-Bu): Build-up from the Ferrio-mesitylphosphane Cp(OC)2Fe-P(Mes)H and Organoisothiocyanates, Quatemization with Alkyl Halides and Oxidation with Sulfur
  3. Phosphenium-Komplexe, 43 [1]. Ringöffnungsreaktionen der dreigliedrigen Phosphametallacyclen {PR2 = P(o-Tol)2, P(Ph)(o-Tol), P(Mes)[C(S)N(H)Et], P(/-Bu)[C(O)N(H)Et} / Phosphenium Complexes, 43 [1]. Ring-Opening Reactions of the Three-Membered Phosphametallacycles {PR1 = P(o-Tol)2, P(Ph)(oTol), P(Mes)[C(S)N(H)Et], P(r-Bu)[C(0)N(H)Et}
  4. Magnesium Bis[D(-)-Mandelate] Dihydrate and Other Alkaline Earth, Alkali, and Zinc Salts of Mandelic Acid
  5. The Basicity of Silylamines and Alkylamines: An Equilibrium Study of the Competitive Borane Adduct Formation
  6. Kristallchemische Beziehungen von CO6O2 [TeO4 (CoAsO5)2] zur Steinsalzstruktur von CoO mit einem Beitrag über magnetische Messungen an CO6O2[TeO4(CoAsO5)2] / Crystal Chemical Relations of Co6O2[TeO4(CoAsO5)2] to the Rocksalt Structure of CoO and a Contribution on Magnetic Measurements of Co6O2[TeO4(CoAsO5)2]
  7. Synthese, Kristallstruktur und Eigenschaften von Triguanidinium-tri--imidocyclotriphosphat-Monohydrat und Tetraguanidinium-tetra-/i-imidocyclotetraphosphat-Tetrahydrat, [C(NH2)3]3(PO2NH)3 · H2O und [C(NH2)3]4(PO2NH)4 · 4 H2O / Synthesis, Crystal Structure, and Properties of Triguanidinium Tri-/i-imidocyclotriphosphate Monohydrate and Tetraguanidinium Tetra-/i-imidocyclotetraphosphate Tetrahydrate, [C(NH2)3]3(PO2NH)3 · H2O and [C(NH2)3]4(PO*NH)4 · 4 H2O
  8. Untersuchungen an Polyhalogeniden, XXXVII [1]. Heptaiodide(3-) von Amminkomplexen des Chroms und Cobalts: Hexamminchrom(III)heptaiodid [Cr(NH3)6](I3)(I4) und die Tri-μ-hydroxo-bis[metall(III)-triammin]heptaiodide [(NH3)3 M(OH)3M(NH3)3](I3)2I mit M = Co, Cr / Studies o f Polyhalides, XXXVII [1]. Heptaiodides(3-) of Ammine Complexes of Chromium and Cobalt: Hexamminechromium(III) heptaiodide [Cr(NH3)6](I3)(I4) and the Tri-μ-hydroxo-bis[metal(III)-triammine] heptaiodides [(NH3)3M(OH)3M(NH3)3](I3)2I with M = Co, Cr
  9. Functionalized 1,1-Ethene Dithiolates as Ligands, V [1]. Synthesis and Crystal Structure of Palladium(II) and Platinum(II) Complexes with Dithioylidene Barbituric Acid Ligands. Molecular Structure of a 2,6-Diaminopyridine-Platinum(II) Barbiturate Complex
  10. Solvothermal Synthesis and Crystal Structure Determination of Tris- (ethyleneamine-ammonium) Tetraselenoantimonat: Non-Centrosymmetry Mediated by an Extended Unusual N-H···N Hydrogen Bonded Network?
  11. Thermische Zersetzung und Lösungskalorimetrie von Ammoniumeuropiumchloriden / Thermal Decomposition and Solution Calorimetry of Ammonium Europium Chlorides
  12. Photochemical Reductive Elimination of Nitrogen from Triazidogallium(III). Generation of Luminescent Gallium(I)
  13. Zur Existenz von [ReNCl4-nFn]- (n = 1-3) Nitridorhenat(VI)-Gemischt- ligandkomplexen -Eine EPR-Untersuchung / EPR Evidence of [ReNCl4-n FnJ– (n = 1-3) Nitridorhenate(VI) Mixed-Ligand Complexes
  14. Synthesis and Crystal Structure of N-[(15,4R)-2-Oxo-pinanyl]-β-alanine Methylester
  15. Synthesis and Conformation of Nucleoside 5'-S-Thiosulfates
  16. Niedere Hydrate aliphatischer primärer Amine. Neue Untersuchungen zu Bildung und Struktur [1] / Lower Hydrates of Aliphatic Primary Amines. New Studies of Formation and Structure [1]
  17. Synthesis and Dimroth Rearrangement of 6-Cyano-l,2,4-triazolo- [4,3-a]pyrimidin-5- and 7-ones. A Novel Alkylation with Orthoesters and a New Participation of the Cyano Group in the Rearrangement
  18. Synthesis and Thermal Properties of Twin Compounds, Alkanediacids 4-(4'-Cyano)-biphenyl Diesters
  19. Synthesis of Pyrrolo-, Thienopyrrolo-, Benzothienopyrroloquinolines as well as Triazoloindole Derivatives
  20. Ab initio MO Optimizations of Osmiumtetracarbonyldihydride and Metallacyclophanes with two Osmium Atoms and their Molecular Complexes with Different Guests
  21. Preparation and Crystal Structure of Cs4Nb2S11
  22. On the Metalation of 2,6-Dimethyl-4-tert-butyl-thiophenol
  23. Kristallstruktur des Oxo-Acetatkomplexes [Co7(μ4- O)2(O2CCH3)10(OPEt3)2] / Crystal Structure of the Oxo-Acetate Complex [Co7(μ4 -O)2(O2CCH3)10(OPEt3)2]
  24. Penol Catalyzed Claisen ortho Ester Rearrangment of Allylic Alcohols with Trimethyl-β-hoxy) ortho Propionate
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